The Giants have been fairly quiet since the start of NFL free agency and aren’t likely to make any big splash, but general manager Jerry Reese said he isn’t done yet.

“There’s still some things to do in free agency for us, I think,” Reese said yesterday on SiriusXM NFL Radio. “We’ve just got to kind of slow-play it a little bit and see who’s out there and what is available for us and what our needs are as we continue the offseason process.’’

Reese said the Giants will “look down the road and see what the draft’s going to bring for us.’’

Perhaps the only glaring hole on the roster is middle linebacker, where free agents Chase Blackburn and Jonathan Goff remain unsigned. As constituted, the Giants would have to turn to Mark Herzlich or Greg Jones entering their second seasons. Reese admitted “I’m not sure’’ when asked who would start in the middle if the season began tomorrow.

“We have some interesting candidates for that job,” Reese said. “We have some young players that we think can step in and do the job. Obviously, Herzlich is a guy we like. We like Greg Jones. There are two young kids that played a lot for us last year until Mark got hurt.’’

Reese also mentioned outside linebacker Michael Boley as a possibility.

Reese admitted losing Mario Manningham in free agency (he signed a two-year deal with the 49ers) was expected.

“The salary cap rules the world,’’ he said. “If you have a lot of good players you just can’t retain them all. That’s just the way it is.’’

Reese also said he expected offensive lineman James Brewer entering his second season to challenge for playing time, possibly as Kareem McKenzie’s replacement as the starting right tackle, and mentioned left tackle David Diehl as “still available for us’’ to move over to the right side if needed.

Reese expressed concern for defensive tackle Marvin Austin, who has missed the past two seasons because of a suspension while at North Carolina and his entire NFL rookie year with a torn pectoral muscle.

“We’re worried about him a little bit,’’ Reese said. “He hasn’t played in such a long time now.’’

* The Giants received some good news yesterday when they were awarded a fourth-round compensatory pick in the NFL Draft, which begins April 26.

The second and third rounds are April 27 and rounds 4-7 take place April 28.

A total of 32 compensatory picks were awarded to 15 teams, the NFL announced. The Jets, Browns and Packers were awarded four compensatory picks.